The CPU can read information from the ROM chip the same way it reads information from RAM. Most of the ROM chips that we use in a PC system for the BIOS are about 64K in size though there is 384k address space available for the BIOS to use. We often refer to BIOS as the BIOS chip, but BIOS is not really the chip itself, it’s the software inside that’s really the BIOS. BIOSīIOS is the collection of programs contained in the ROM chip. Those programs stored on the ROM Chip are collectively referred to as the Basic Input/Output Services or BIOS chip. These devices include the keyboard, disk drives, memory, etc. ROM chips that are installed on the motherboard contain programs that were burned into that ROM, that allow the CPU to communicate the with various devices attached to the motherboard. In contrast to ROM, a RAM chip loses it’s contents when the PC’s turned off. ROM stands for Read Only Memory, and this kind of chip retains it’s contents even if the system is powered off. To enable our CPU to communicate with other devices on our motherboard, we implement a special chip on the motherboard called a ROM chip. Key terms: device, chip, cpu, memory, parameter, motherboard, battery, post, load, data, power, address, software, firmware Objectives: Learn the difference between BIOS and CMOS.
